Robert Barker/University Photography

David Wrenner, 4, watches a ball float above an air stream provided by graduate student David Tsang, left, with physics senior lecturer Phil Krasicky looking on. Krasicky taught Cornell alumni and their families about electromagnetism, conservation of energy, air pressure and other physical phenomena in a demonstration-packed talk in Schwartz Auditorium, June 9. Copyright © Cornell University

There was a levitating beach ball. A fluorescent tube that glowed without being touched. Big poofs of liquid nitrogen vapor in perfect halo-like rings, shooting out from a wooden box into the audience.

Phil Krasicky has accumulated a giant bag of tricks over his years as a senior lecturer at Cornell, from gyroscopes and oscillators to pendulums and jumping pie pans. And he brought them all to Schwartz Auditorium for a stunt-filled lecture to alumni on the first day of Reunion Weekend on Friday, June 9.

Some audience members were alumni from the 1960s. Others were a few years short of kindergarten. They all had -- well, a blast.

The biggest hit, by far, was Krasicky's finale: Cornell's Alma Mater, played in harmony as Krasicky rubbed his fingers over the rims of more than 20 wine glasses: a counter full of them, each perfectly tuned (with a turkey baster) with just the right amount of water. Listen to the performance . . .