My daughter Ilana sent me this picture and wondered what it was. I definitively answered that it used to hold a call box for emergencies. After looking a little closer, now I’m not so sure. And the last thing I want to do is lie to my daughter! Can you help?

Dave Adler, Annandale

During World War II, many American towns and cities were stripped of their scrap metal. Old bits of iron, steel and tin — whether in the form of soup cans, Civil War cannons or fences — were collected, melted down and turned into bombers and battleships.

But not the distinctive cast-iron columns standing sentinel on the street corners of Washington and other cities. Why not? Because they were still in use, part of an elaborate communications system that dated to a time before 911, when few homes and businesses had telephones.

The District’s fire department first employed them in 1864, said Jim Embrey, a retired D.C. firefighter and curator at the D.C. Fire and EMS Museum. 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.

Once a box was opened, the citizen would turn a wheel inside. Cut into the wheel were notches that tripped a telegraph key. The wheel was unique to that box. For example, three notches, a space, two notches, a space, then four notches would correspond to Box 324.

A telegraph signal was sent directly to the District’s alarm headquarters, which in turn would forward it to all fire stations. Firefighters would listen to see whether it was a box they were responsible for.

There was a problem.

“When people see a house on fire, they get a tad excited,” Jim said. Often, bystanders would crank the wheel as fast as they could, thinking the faster they cranked, the sooner help would come.

“But that would simply run all the numbers together,” Jim said. “They would crank so fast that there would be no spaces. Headquarters had no idea what box was being pulled.”

In 1873, the fire department started installing boxes made by Gamewell, a Massachusetts company that came to dominate the call-box industry. When a Gamewell box was pulled, it tripped a clockwork mechanism that automatically transmitted the box number at a steady pace.

Fire chiefs had keys they could use to open a different section of the box, access a telegraph key and tap out a call for additional help.

“Sometimes it’s confusing when people see one call box right next to another,” said D.C. historian Paul K. Williams. “That’s because one was a police box and one was a fire box.”

Fire boxes were painted red. Police boxes were painted blue. Designs of the box and the column it sat on could vary. Typically, fire boxes were shaped like little houses. Police boxes were rectangular, with rounded corners.

While fire boxes were meant to be used by the public to report fires, police boxes were for police use. Officers on foot patrol had brass keys they used to open the boxes on their beat and report back to their precinct, first telegraphically and later by telephone. Lifting the receiver would connect with a switchboard operator who would note the time the officer had checked in.

If an officer didn’t check in, police cars would be sent on a search.

Paul said one retired officer he spoke with told him he had once handcuffed a suspect to one of the boxes, then telephoned the station to order a wagon be sent to that box.

The advent of radios in police cars and on fire equipment in the 1950s spelled the end of the call boxes. But it was a slow departure. Jim, of the fire museum, said the fire department’s boxes were in use until the 1980s. That’s more than 100 years of service — amazing, when you think about how quickly today’s computer-based products go out of date.

At their peak, there were about 1,500 boxes in the District. In 2000, the city prepared to gather up the 700 or so that were still on the street, their mechanisms removed. That’s when Cultural Tourism D.C. suggested turning some into works of art reflecting the communities in which they stood. The District’s Department of Transportation painted primer on the survivors, stabilizing them.

By the time the “Art on Call” project wrapped up in 2009, 145 boxes had been transformed in such neighborhoods as Mount Pleasant, Sheridan/Kalorama and Capitol Hill.

Other communities have continued in the spirit. Six call boxes in the Foxhall neighborhood were renovated recently.

Paul worked on the original Cultural Tourism D.C. project, researching the history of these fetching examples of street furniture.

“Once you notice one, you’ll notice them all,” he said. “You’ll keep seeing them.”

Twitter: @johnkelly

For previous columns, visit washingtonpost.com/john-kelly.