For the life of me, I can't think of what the difference is offhand between the pendulum at the pole, where the pivot is on the earth's ratation axis, and the ones mention and one similar that I think is in the Smithsonian Ist. in Wash. DC. I'm not going to drag out my Eulerian angle transformations and try to transform the omega cross velocity from pole case to get the local coordinate non-pole case equations and try to solve them. Feynman I once saw, and heard give a paper at a symposium (practically none of which I understood), but I never read anything by him, as I did't need his new quantum mechanics to treat my problems, and older quantum mechanics wasn't all that simple for me to start with. (Feynman's talk was far far the only such that I merely attempted to show that I wasn't sleeping, although that would have been more profitable for me at the time.)

Bogolieubof and K. Marterosin on QM at the International Congress on Theoretical Physics (I was still a chemist then), S. Charandraseker (the physics one), Marcel Ries on general relativity, E. Wigner and J. Robert Oppenheimer at Princeton on Einsein- Van Vleck, L. Pauling (Nobels)an others on QM, H. Kittell on solid physic, there were lots. Including Peter Debye (I an undergrad.). C. V. Raman's son was just a lab visitor. I wasn't much of a theoretian, but on a few rare occasions had to correct some older theory a bit.