Today in History. : On Dec. 3, 1984, thousands of people died after a cloud of methyl isocyanate gas escaped from a pesticide plant operated by a Union Carbide subsidiary in Bhopal, India. In 1833, Oberlin College in Ohio — the first truly coeducational school of higher learning in the United States — began holding classes. In 1926, English mystery writer Agatha Christie, 36, disappeared after driving away from her home in Sunningdale, Berkshire. (Christie turned up 11 days later at a hotel in Harrogate, Yorkshire.)