Downhill Test Run

Indoor catapults are great, but man, I needed real speed! I dragged a discarded glossy postcard and propped it over the wooden threshold between the living room and the hallway to build a drop-in ramp. Under the credenza, I scavenged a red plastic toy roller skate with loose metal axles. I gave it a solid test kick from behind, and whoosh—it caught the lip of the cardboard, rocketed over the wooden crest, and went skittering straight down the hallway floorboards with an echoing rattle. Now that is pure velocity!