Monday, June 26th, 2017

Downie, the undisputed maestro of Saturday science, here reveals important principles in physics, engineering, and chemistry through such marvels as the Helevator–a contraption that’s half helicopter, half elevator–and the Rocket Railroad, which pumps propellant up from its own track. The Riddle of the Sands demonstrates why some granular materials form steep cones when poured while others collapse in an avalanche. The Sunbeam Exploder creates a combustible delivery system