Methods of Integration which Preserve the Contact Transformation Property of the Hamilton Equations

The well known 1956 unpublished report by De Vogelaere, motivated by the physics of particle accelerators, is the first demonstration of the existence of numerical integrators (now called symplectic integrators) that preserve a basic property of Hamiltonian systems. The purpose of this short note is to introduce René De Vogelaere, list his pioneering accomplishments, and relate them to other early work on symplectic integrators. The preprint itself, typset in LaTeX, is attached as an appendix.