Benjamin Donn (1729 - 1798), sometimes known as Benjamin Donne, was a British cartographer, surveyor, and mathematician active in England during the middle to late 18th century. Born in Bidford, England, Benjamin Donn was the heir to long line of well-respected mathematicians, including his father and older brother, who ran a local school. Early on he developed an interest in surveying and astronomy and from 1749 to 1756 was a regular contributor to the "Gentleman's Diary" where he published accounts of his astronomical observations. In 1768 he was elected librarian of the Bristol Library, and, "in keeping with his taste for the binomial theorem and the book of Euclid, he conceived the idea of converting the establishment into a mathematical academy; but the corporation did not join in his enthusiasm, and students were not invited." Later he established his own private mathematical academy in Bristol near St. Michael's Church. Cartographically, Donn's most significant work is his 1765 large format map of Devonshire, based upon a mile for mile survey he completed at his own expense. This was the first large scale map of any British county and won Donn lasting fame as well as a £100 gratuity from the Royal Society for the Arts. Donn later went on to publish a number of other less significant but popular maps including a pocket map of Bristol, a map of western England, and several nautical charts of the Western Ocean, as well as various mathematical tables. A lifetime of study and dedication to mathematics earned Donne the title of Master of Mechanics to the King, an honorarium he would hold for only a short time. Donn died in 1798.