John Keats Quote

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, as it erewhile made
The tender-person'd Lamia melt into a shade.

"Lamia", Pt. II, l. 229. - Poems (1820)