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 true that this man was nothing but an elemental force in motion, directed and rendered more effective by extreme cunning and by a relentless tactical clairvoyance .... Hitler was history in its purest form.”
—Albert Camus (1913–1960)
“America is the only nation in history which miraculously has gone directly from barbarism to degeneration without the usual interval of civilization.”
—Georges Clemenceau (1841–1929)
“The history of persecution is a history of endeavors to cheat nature, to make water run up hill, to twist a rope of sand.”
—Ralph Waldo Emerson (1803–1882)