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Events on Wednesday 9 January 1799 4
1718 – 1799Maria Gaetana Agnesi (1718-1799)Died 9 January 1799, aged 80Italian mathematician whose Instituzioni analitiche was one of the first textbooks to cover both differential and integral calculus. The curve known as the witch of Agnesi is named after her. She later gave up mathematics to devote herself to charity in Milan.
1718 – 1799Maria Gaetana Agnesi (1718-1799)Died 9 January 1799, aged 80Italian mathematician whose Instituzioni analitiche was one of the first textbooks to cover both differential and integral calculus. The curve known as the witch of Agnesi is named after her. She later gave up mathematics to devote herself to charity in Milan.
1799Britain introduces income taxPitt's graduated tax to fund the war with FranceWilliam Pitt the Younger brought in Britain's first general income tax to pay for the French Revolutionary Wars. It was graduated, charging up to two shillings in the pound on incomes over £200. It was repealed in 1802 and later reintroduced.
1799Britain introduces income taxPitt's graduated tax to fund the war with FranceWilliam Pitt the Younger brought in Britain's first general income tax to pay for the French Revolutionary Wars. It was graduated, charging up to two shillings in the pound on incomes over £200. It was repealed in 1802 and later reintroduced.