Change: Presents science’s grand laws of conservation by looking at what remains unchanged in processes as complex as the three-week-long Tour de France bicycle race and a three-foot lucite box packed with Rube Goldberg-type contraptions that spin and bump and explode when triggered. Energy is measured in a blaze of jelly donut units; mass is measured in terms of the weight of the dot over the letter i. And eventually, both constants are unified by Morrison as he uses a little orange wind-up kangaroo to discuss Einstein’s famous formula, E=mc2.