Sir William Curtis (25 January 1752 – 18 January 1829) was born in Wapping, London, the son of a sea biscuit manufacturer.
MP for any years, Alderman of the city, becoming Sheriff of London in 1788 and Lord Mayor in 1795–96. He was created a Baronet of Cullonds Grove in 1802.
The definition of the three Rs as "reading, writing, and 'rithmetic" is attributed to him from a speech made at a Board of education dinner.
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