CALLBX_230215_16
Existing comment: Fire alarm boxes such as this one (originally painted red) were installed in the District after the Civil War. Telegraphs transmitted the box number (top) to a fire alarm center. This system was used until the 1970s when the boxes were converted to a telephone system. By the 1990s, the callbox system had been replaced by the 911 system and was abandoned.
Modify description