BONNYCASTLE, John. 11819 Autograph Letter Signed, making detailed arrangements for the payment of rent, reporting an improvement in health, etc. A good one page example, 9 x 7 inches. Woolwich Common, 2 April 1817. John Bonnycastle (1750-1821), Professor of Mathematics at the Royal Military College, Woolwich, author of several works on elementary mathematics. Leigh Hunt used to meet him in the company of his great friend Fuseli, and has left a description of him in his book on Lord Byron and his Contemporaries.