Odd cannonball keeps history buffs guessing

Brent Hamilton thought he had a nice conversation piece in his Broad Street garden: an old cannonball left over from the Siege of Charleston.

As it turns out, that was only half-right. Wrong century, wrong siege.

Landscapers unearthed the 5.5-inch cannonball while uprooting a Washingtonia Palm from the doctor's backyard recently. It was just 14 inches beneath the surface and remarkably well-preserved. Initially, no one thought much of it -- Civil War-era ammunition turns up from time to time.

But a chance remark led Hamilton to call in experts, and it turns out they believe the ordnance could be a British cannonball fired into the city during the Revolutionary War.

"It sat in the flower bed for six months," Hamilton said. "We didn't think much of it. But when our home was on the House Tour, someone said we should call the Preservation Society."

Keith Purdy, a local artillery expert, said Hamilton has a Colonial-era cannonball, probably British, and perhaps fired at Charleston from James Island. It is a solid ball, so no danger of explosion. Sometimes when Civil War-era ordnance is found, the bomb squad has to check it out because there is a chance that even 150-year-old ammunition could detonate.

This was just a projectile.

"It was probably fired by a mortar or howitzer," Purdy said. "It's not uncommon to find this size of cannonball, but not from the 18th century."

The British Army opened fire on Charleston in late March 1780, beginning a six-week siege that ultimately would end with the capture of the city. The British Army fired on the city from above the siege line, midway up the peninsula, and from a couple of batteries on James Island (one of them near present-day Harbor View Road, where Mimi's Cafe once stood). One British shot fired from there famously took the arm off a statue of William Pitt, the former British prime minister, that stood in the Four Corners of Law.

Carl P. Borick, assistant director of the Charleston Museum and author of "A Gallant Defense: The Siege of Charleston, 1780," said the cannonball is without question from the 18th century. But that's not the end of the story.

"It really doesn't fit the pattern for a Revolutionary War piece," Borick said. "It's kind of a mystery."

That's because the British had precise weights for their cannonballs -- 6, 12, 18 and 24 pounds. They were standardized for cannons. This particular cannonball, however, weighs 22 pounds. Borick said the Broad Street area around Hamilton's home would have caught cannon fire from James Island, but the odd weight of the shot makes it hard to say for sure this is from one of those batteries. The museum has never found a cannonball with its weight off by as much as two pounds.

"That makes me somewhat skeptical," Borick said.

Experts might assume the ball lost weight due to deterioration during its 230 years planted in the ground -- it has happened before -- but this one seems too well-preserved for that. Purdy said the roots of the palm tree may have kept water off the iron ball, but he can't explain the odd weight. Basically, it is a mystery that might never be solved.

Hamilton said that whatever his cannonball is, he wants to share it with locals. He plans to lend it to the Old Exchange Building for public display later this year.