Secret Philly

Secret Philly: How the City Hall clocks adjust for Daylight Saving Time

The 235-pound minute hands have to be manually moved.

City Hall clock tower, from the inside looking out

City Hall clock tower, from the inside looking out

Courtesy City Hall Visitor Center & Tours

Originally published March 2018; updated November 2019

When it’s time for the clock at the center of Philadelphia to skip forward or back an hour, Joseph Brasky is the man responsible.

At 2 a.m. this Sunday morning, Brasky will be inside the City Hall tower, manually cranking a 15-foot, 235-pound minute hand to adjust for Daylight Saving Time.

Brasky, a City Hall public properties maintenance staff member, is Philly’s clock guy. He was taught by Lancaster clockmaker Bob Desrochers to properly wind each of the four timepieces at the intersection of Broad and Market, turning them forward or backward when the seasons change.

It’s not that all that difficult a process, per City Hall Director of Building Services Richard Mariano. But it is tedious.

There are four clock faces in the tower, one each looking north, east, south and west. After Brasky cuts the power — or “stops the escapement,” for those fluent in clockspeak — he must crank forward each minute hand individually.

Accuracy is critical. “The challenge is lining all four clocks up,” Mariano said

After manually moving the giant metal pointers, Brasky will take a quick walk around the outside of the building, checking that the time on each clock is exactly right. If one clock is wrong, if it’s even 30 seconds off, he’s back up in the tower for round two.

In the early 1900s, people counted on the City Hall clock to keep in sync

In the early 1900s, people counted on the City Hall clock to keep in sync

Air-powered clock hands were tough to control

Brasky’s task isn’t as daunting as it used to be. City Hall’s current chronometers were installed in 1947, according to clockmaker Desroshers.

Currently, the mechanics controlling the clock hands run using electricity, so it’s not difficult to stop their motion by cutting the power if you want to adjust the time.

But before 1947, Deroshers said, the City Hall clocks operated on a pneumatic system, meaning they were powered by air — which is much harder to control, and even tougher to set forward and back with accuracy.

Switching to a reliable system was at one point essential, he noted.

“Large clocks like this were originally intended to be kind of a regulator,” Deroshers explained. “You knew what time it was, so you could adjust your time piece to keep up with it.” Now people use their phones, he admitted, instead of needing an external point of reference to stay in sync.

But the work Brasky does to make sure the City Hall clocks display correctly is still useful, Deroshers said: “It’s important to maintain that timekeeping.”

Want some more? Explore other Secret Philly stories.

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