A slipped metal rule gave us the cardboard box
Pre-cut cardboard owes a great deal to an accident. In the 1870s Robert Gair, a Brooklyn printer and paper-bag maker, watched a shifted metal rule slice through a run of bags instead of creasing them, and realised that cutting and creasing in one pass could turn flat board into ready-shaped boxes. Cardboard fixtures such as this wood-grain keychain display stand descend directly from that idea.
