Erratum: “On trajectories of rolling marbles in cones and other funnels” [Am. J. Phys. 81, 890–898 (2013)]

In a gracious communication, Germain Rousseaux points out that the problem of a ball moving in a cone has a much older pedigree than I acknowledged in my recent article in this journal,¹ playing a significant role in the dialogue between Hooke and Newton, and even in the publication of the Principia. Rousseaux and colleagues relate a fascinating analogy—how a ball sliding frictionlessly in a tilted cone in a vertical gravitational field mimics the three-body problem with the ball playing the role of the moon, the conical surface providing an analogy to the Earth's attractive force on the moon, and the tilt modeling the solar influence on the pair—and show that chaotic motion can result if the tilt angle is large. They explore this idea theoretically and experimentally(!) in their recent publications,^2,3 and revisit some of the remarkable history of this intriguing problem, citing other papers of interest—Nauenberg's...