After numerous accidents where the Illinois Central Railroad crossed Highway 7 near Grenada, Mississippi, in the 1930s, inventor Alonzo Billups came up with a one-of-a-kind solution. When a train approached the crossing, motorists were confronted with a lighted skull and crossbones, the glowing words “Stop-DEATH-Stop,” flashing neon arrows indicating the train’s direction, and an air raid siren.

The video here is a simulation; the actual gantry was removed due to a scarcity of neon in the war years. But two photographs survive.