Cambridge: Parker, 1848. First separate edition. Outer leaves soiled. Two holes punched at left margin for insertion into a binder. A good copy. Protected in a special offprint envelope/folder. Disbound. Quarto. [2, blank], 10 pp. Item #8027
De Morgan’s (1806-71) name is usually associated with his work in symbolic logic. However, he made influential contributions to many fields of mathematics, including geometry and differential equations. In this paper De Morgan demonstrates his keen interests in computational methods. Building on an old method by Legendre, he proposes two new approaches to solving partial differential equations, using an intricate change of variables. Volumes of the Transactions of the Cambridge Philosophical Society, where De Morgan published most of his logical papers, are very rare. Separate authors’ offprints from this publication are hardly ever seen.