He was showing changes in pitch with a tuning fork placed in water. He said, "When you put the tip in, it vibrates. The short fork makes a lower pitch. And the longer fork makes a higher pitch. So the size changes the pitch." He was talking about chemical bonds and said, "When they're long and hard, they're stronger than when they're soft. " And then, "When things are rubbed together, friction is produced" and then rubbed a rod with a fur pelt to show magnetism through friction.