The earliest boxes were locked, the keys held by nearby merchants who could be summoned by a bystander at the first sign of a blaze. For example, three notches, a space, two notches, a space, then four notches would correspond to Box 324. “That’s because one was a police box and one was a fire box.”Fire boxes were painted red. ADWhile fire boxes were meant to be used by the public to report fires, police boxes were for police use. The advent of radios in police cars and on fire equipment in the 1950s spelled the end of the call boxes.

Source: Washington Post January 23, 2021 21:33 UTC