• Name: Bonnycastle, Professor Charles
• Gender: Male
• Birth Date: 22  November  1796
• Death Date: 31  October  1840
• Occupation: university lecturer

Bonnycastle became the first professor of natural philosophy at the University of Virginia at its opening in 1825. He subsequently became the second professor of mathematics when the postholder, Thomas Key, resigned. Having previously contributed to the thirteenth edition of his father's Introduction to Algebra (1824), Bonnycastle published his own textbook Inductive Geometry in 1834. He also contributed to the Transactions of the American Philosophical Society. He was the son of John Bonnycastle, also a mathematician.

An entry dated 4 August 1807 - '[John] Bonnycastle and son' could be Charles but John had other sons, so it has been left uncoded. Moreover, a letter from Godwin to Mary Jane in September 1819 says that he met (as for the first time) Charles Bonneycastle, who had been examining candidates for works on Naval Architecture and whom Godwin thought possibly more appropriate for teaching his son William than his father (John), who had been giving William lessons.

• MS. Abinger c. 43, fol.6: 8 Sept. 1819
• DNB
• 'Charles Bonnycastle' at the University of Virginia website.

This table lists the people this person is most frequently noted with in the diary.