Carl Gustav Jacob Jacobi, from 1826 a professor of mathematics at Königsberg University and a prolific writer, publishes “Fundamenta nova theoria functionum ellipticarum” (“New Foundations of the Theory of Elliptic Functions”) in 1829.

This classic treatise on elliptic functions is of great importance in mathematical physics, because of the need to "integrate second order kinetic energy equations.”

The motion equations in rotational form are integrable only for the three cases of the pendulum, the symmetric top in a gravitational field, and a freely spinning body, wherein solutions are in terms of elliptic functions.