The 19th-century brick vent shaft stands in Judiciary Square. The shaft once drew air into a nearby courthouse. It was removed during a 2006 renovation of the D.C. Court of Appeals and then put back next to the stone and glass entrance to a new underground parking garage. (John Kelly/The Washington Post)
Columnist

A strange brick tower sits near the D.C. Court of Appeals. It looks real old. Can you find out what it is and why it is still there?

Mary Frances Ronan, Alexandria, Va.

Imagine, if you will, a “Mission: Impossible”-type movie set in the early 20th century. The Impossible Missions team must thwart an attempt to kidnap President Theodore Roosevelt that they know will take place at the District Courthouse at Fifth and Indiana NW.

Actually, what the team wants is to spirit Roosevelt away and replace him with a body double — one of their operatives wearing a lifelike gutta-percha mask (fashioned by sculptor Daniel Chester French, as it happens). Once kidnapped, the fake Teddy will be able to infiltrate the criminal ring, which is working at the behest of wealthy railroad magnates opposed to Roosevelt’s trust-busting.

With Answer Man so far?

But how to slip in and out of the building unseen? Well, how does any commando get into a building? Through a ventilation shaft, of course. And that is what that tower is.

The building that is today the D.C. Court of Appeals was designed by architect George Hadfield and built in 1820, originally to serve as Washington’s City Hall. The brick tower itself was not erected until the 1880s, when the building housed various courts as well as the Civil Service Commission. (And who served on that commission and had an office there? That’s right: Teddy Roosevelt.)

The tower was part of a system that sucked in fresh air and pumped it through the building.

“Beneath it was a horizontal tunnel big enough for a person to walk through,” said Chris Wiley, project manager at Beyer Blinder Belle, the architectural firm responsible for the courthouse’s 2005 renovation. “It entered the lower level of the courthouse through the foundation walls and went to the mechanical equipment room.”

It was not air conditioning, per se, but it did allow air to move around, providing some relief from Washington’s sultry summers.

In the recent renovation, Beyer Blinder Belle architect Hany Hassan moved the courthouse entrance from the south side to the north side and placed a handsome glass box facing E Street NW.

An underground parking garage was also added as part of the renovation. That required temporarily moving the brick vent shaft and the nearby Darlington Memorial Fountain.

The shaft, Hassan said, was completely covered with ivy “to the point that it almost looked like a shrub of sorts. You couldn’t even see the structure.”

Some people involved with the project thought that the tower — about eight feet wide and 14 feet tall — should have been taken apart and then reassembled.

“I said absolutely not,” said Hassan, who was impressed by the circular perfection of the tower, its fine brickwork, thin bands of mortar and slate capstone. “I knew if they dismantled it, it would never come back together again.”

Instead, workers were able to dig around the shaft’s foundation, make a couple of holes and insert steel beams to support the structure. (They’re called needle beams.) The tower was welded inside a steel frame, then lifted up with a crane by United Rigging and set down nearby.

There it sat for a couple of years as the parking garage was completed. The tower was put back in almost the same place, just a few feet over. It sits next to a small glass and stone building that serves as the elevator and stair enclosure for the parking garage. (The Darlington Memorial Fountain was also restored.)

Hassan said he never considered demolishing the shaft and carting away its remains. One reason: It was a reminder that the exterior of the nearby courthouse was originally brick covered in stucco. It didn’t receive its Indiana limestone skin until a renovation in 1917.

Fittingly, Hassan was able to figure out a way to use the tower. Although the courthouse’s modern HVAC system doesn’t need the shaft to draw in fresh air, it does need it to vent air out.

“We have to exchange warm air,” Wiley said. “All we did was change the air flow. It used to suck it in. Now it blows it out.”

On a cold day, you can see what looks like steam rising from the tower. It’s vapor from the air that’s being exhausted. And it’s a reminder of the craftsmen who nearly 140 years ago painstakingly created something that possesses the beauty that can come with utility.

The tower, said Hassan, “was not viewed as being an element of importance. I viewed it as being very precious.”

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