The Rainbow Passage

rp-01 When the sunlight strikes raindrops in the air,
rp-02 they act as a prism and form a rainbow.
rp-03 The rainbow is a division of white light into many beautiful colors.
rp-04 These take the shape of a long round arch, with its path high above,
rp-05 and its two ends apparently beyond the horizon.
rp-06 There is , according to legend, a boiling pot of gold at one end.
rp-07 People look, but no one ever finds it.
rp-08 When a man looks for something beyond his reach,
rp-09 his friends say he is looking for the pot of gold at the end of the rainbow.
rp-10 Throughout the centuries people have explained the rainbow in various ways.
rp-11 Some have accepted it as a miracle without physical explanation.
rp-12 To the Hebrews it was a token that there would be no more universal floods.
rp-13 The Greeks used to imagine that it was a sign
rp-14 from the gods to foretell war or heavy rain.
rp-15 The Norsemen considered the rainbow as a bridge
rp-16 over which the gods passed from earth to their home in the sky.
rp-17 Others have tried to explain the phenomenon physically.
rp-18 Aristotle thought that the rainbow was caused by
rp-19 reflection of the sun's rays by the rain.
rp-20 Since then physicists have found that it is not reflection,
rp-21 but refraction by the raindrops which causes the rainbows.
rp-22 Many complicated ideas about the rainbow have been formed.
rp-23 The difference in the rainbow depends considerably upon the size of the drops,
rp-24 and the width of the colored band increases as the size of the drops increases.
rp-25 The actual primary rainbow observed is said to be the effect of
rp-26 super-imposition of a number of bows.
rp-27 If the red of the second bow falls upon the green of the first,
rp-28 the result is to give a bow with an abnormally wide yellow band,
rp-29 since red and green light when mixed form yellow.
rp-30 This is a very common type of bow, one showing mainly red and yellow,
rp-31 with little or no green or blue.