There are various sites about rainbows and related atmospheric effects, e.g. the excellent Atmospheric Optics site. A recent addition is an extraordinary nacreous cloudscape in Iceland, whilst elsewhere there are images of a glory and broken spectre in Ireland, a low bow in Australia and a moon bow in Hawaii. The site provides technical information and software for simulating different optical effects: HaloSim. There is also some history: Lowitz arcs are named after Tobias Lowitz, who sketched a complex display visible from St Petersburg on June 18th 1790, and Parry arcs were first recorded by William Perry on 8 April 1820, near Melvile Island in the Candian Arctic, during the search for the Northwest Passage.
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May I add a couple of poetic references to your excellent postings on rainbows? A poem of William Wordsworth from 1802, "My Heart Leaps Up When I Behold The Rainbow", begins:
My heart leaps up when I behold
A rainbow in the sky:
So was it when my life began;
So is it now I am a man;
So be it when I shall grow old,
Or let me die!…
Keats, though, did not approve of the Newton's scientific deconstruction of the rainbow as his poem "Lamia" of 1820 demonstrates:
Do not all charms fly
At the mere touch of cold philosophy?
There was an awful rainbow once in heaven:
We know her woof, her texture; she is given
In the dull catalogue of common things.
Philosophy will clip an Angel's wings,
Conquer all mysteries by rule and line,
Empty the haunted air, and gnomed mine –
Unweave a rainbow
Thanks Aurelia. John Gage starts his chapter with the Keats quote. He also notes that it was Keats and Charles Lamb who had voiced regret at Newton's unweaving of the rainbow during the 'immortal dinner' with Haydon and Worsdsworth on 28 December 1817.
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