Then, in the 1850s, corrugated cardboard: paperboard folded vertically in arches and smooshed between two horizontal planes like a sandwich. The interior curve gives the material a disproportionate strength. And so inside every flap of cardboard is the science of the cathedral, ten thousand vaulted arches distributing compression, allowing pulp to transcend into something lightweight, rigid, and, above all, cheap. It is the stuff of revolutions.
