The Fog Bell — What is resonance, and why does timing beat strength?

Resonance is what happens when you push something at exactly the rhythm it already wants to move at: each small push adds to the last one, and tiny pushes stack up into an enormous swing. Push at the wrong moment and even a huge shove takes the swing away instead. It is why a child can send a friend high on a swing with one finger, why a bell ringer can move a bell that weighs more than a car, why an opera singer can crack a glass, and why soldiers are told to break step before they march over a bridge. Ring a little bell in a fog tower, find the great bell's slower beat with no clue but the rope in your hand, and then cross a bouncing rope bridge where staying off the beat is the only way home.