In 1518, Strasbourg experienced a bizarre "dancing plague" where hundreds danced uncontrollably for weeks. In 1726, Mary Toft convinced England she gave birth to rabbits, sparking a media frenzy. In 1838, the UK issued the world's first prepaid postage stamp, the Penny Black. In 1904, Helen Keller, despite being deaf and blind, graduated from Radcliffe College, changing perceptions on disability. In 1971, the US converted its currency from 40% silver to a copper-nickel alloy, marking the end of silver coins in circulation.