This artillery piece was given as a gift to NYC back during the Civil War, but when workers recently removed the concrete that had sealed the 230-year-old cannon, they found that it was loaded with a cannonball and gun powder. (Photo: CBS 2)

NEW YORK (CBSNewYork) — A dangerous and historic discovery was made in Central Park on Friday afternoon.

Parks workers came upon a live cannon ball, loaded in a cannon that is getting refurbished, CBS 2’s Lou Young reported exclusively.

The loaded artillery piece was one of two Revolutionary War-era cannons being stored at the park’s Ramble shed near the 79th Street transverse. Preservation workers for the Central Park Conservancy called police about mid-day after opening up the capped cannon for cleaning.

The NYPD released a picture of what its officers found: more than 800 grams of black powder still capable of firing, along with cotton wadding and a cannonball CBS 2’s Young spotted being carried in a white cloth by a Conservancy employee.

For John Moore, who is working on a book called “The Secrets of Central Park,” this is a new one.

“This is an amazing surprise. It was there for so many years and people were sitting on it when it was a loaded cannon,” Moore said.

That’s right: the loaded cannon was on public display from the 1860s until 1996 when the Conservancy decided to bring it indoors to protect it from vandalism. It was donated to the park about the time of the Civil War.

The finding was a shock to everyone involved, including tourists using the park Friday afternoon.

“Something like that, it’s surprising to be overlooked,” Denise Night said.

“It seems like some people are pretty incompetent not to notice after all these years,” Steve Night added.

In fairness, it never occurred to anyone that the cannon, which is said to be at least 233 years old, would still pose a threat. The field piece was already more than 90 years old when it was donated to the park, apparently by someone who’d salvaged it from a sunken British frigate in the East River. It was put on display at the park, and capped with concrete. No one even considered the possibility that British sailors had loaded and sealed it before their ship went down.

In the end, police removed the powder, but left the cannonball, all the while taking a lighthearted approach to the incident.

“We silenced British cannon fire in 1776 and we don’t want to hear it again in Central Park,” the NYPD said in a statement.

It’s probably safe to say, that’s the last one in Central Park.

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