History
Psoralens have been known since ancient Egypt but have only been available in a chemically synthesized form since the 1970s.
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Famous quotes containing the word history:
“It is remarkable how closely the history of the apple tree is connected with that of man.”
—Henry David Thoreau (1817–1862)
“... that there is no other way,
That the history of creation proceeds according to
Stringent laws, and that things
Do get done in this way, but never the things
We set out to accomplish and wanted so desperately
To see come into being.”
—John Ashbery (b. 1927)
“He wrote in prison, not a History of the World, like Raleigh, but an American book which I think will live longer than that. I do not know of such words, uttered under such circumstances, and so copiously withal, in Roman or English or any history.”
—Henry David Thoreau (1817–1862)