Near Key West in Monroe County, Florida — The American South (South Atlantic)

Red-Hot Cannonballs

Fort Jefferson

— Dry Tortugas National Park —

Red-Hot Cannonballs Marker image. Click for full size.

Photographed by Vince Jackson, March 4, 2022

1. Red-Hot Cannonballs Marker

Inscription. Imagine what it was like to heat solid cannonballs in a hot shot furnace like this one, so gun crews could fire red-hot projectiles at wooden warships to set them ablaze. This process involved several soldiers. One soldier maintained the coal fire and loaded the cannonballs. After 30 minutes, a second soldier removed the heated balls with tongs, and a third cleaned them with a rasp. Others carried them in ladles to the guns around the fort.

The idea of setting fire to enemy warships can be traced back to the ancient world. The advent of explosive shot and ironclad ships in the Civil War eventually rendered this kind of furnace obsolete. Oceangoing ironclads, however, were not common, so this hot-shot furnace was viable for use against wooden ships long after the war.

(captions)
Historic hot shot furnace before it was rebuilt
The hot shot furnace was completed in 1863 and refurbished in 2004. It is believed to br the largest—and the last—hot shot furnace built in the United States.

Erected by National Park Service, U.S. Department of the Interior.

Topics. This historical marker is listed in these topic

Paid Advertisement

Click or scan to see
this page online

lists: Forts and Castles • Parks & Recreational Areas • War, US Civil.

Location. 24° 37.774′ N, 82° 52.391′ W. Marker is near Key West, Florida, in Monroe County. It can be reached from no nearby street. Touch for map. Marker is at or near this postal address: Fort Jefferson - Key West, Key West FL 33040, United States of America. Touch for directions.

Regionally, this marker is on the Florida Keys.

It is also in the American South

and on the Gulf Coast.

Globally, it is in the North Atlantic Region,

North America,

a Gulf of Mexico state,

the Western Hemisphere,

the Western World,

and the Anglosphere.

Historically, it finds itself in what was once New Spain,

the territory of the Mississippian Culture,

one of the Confederate States of America,

and the Antebellum South.

Other nearby markers. At least 8 other markers are within walking distance of this marker: Parade Ground Panorama (a few steps from this marker); The Moat (within shouting distance of this marker); An Island of Civility (within shouting distance of this marker); Keeping Powder Dry and Safe (within

Photographed by Vince Jackson, March 4, 2022

2. Red-Hot Cannonballs Marker

shouting distance of this marker); The Hospital (within shouting distance of this marker); Defending US Commerce (about 300 feet away, measured in a direct line); Catching Rain (about 400 feet away); In Memory of Brevet Major, Jos. Sim Smith (about 400 feet away). Touch for a list and map of all markers in Key West.

Also see . . . Dry Tortugas National Park. National Park Service (Submitted on March 14, 2022.)

Fort Jefferson's Shot Furnace image. Click for full size.

Photographed by Vince Jackson, March 4, 2022

3. Fort Jefferson's Shot Furnace

Interior of the hot-shot furnace image. Click for full size.

Photographed by Pete Skillman, November 20, 2023

4. Interior of the hot-shot furnace

Credits. This page was last revised on February 1, 2024. It was originally submitted on March 11, 2022, by Vince Jackson of Toano, Virginia. This page has been viewed 1,396 times since then and 171 times this year. Photos: 1, 2, 3. submitted on March 11, 2022, by Vince Jackson of Toano, Virginia. 4. submitted on January 29, 2024, by Pete Skillman of Townsend, Delaware. • Bernard Fisher was the editor who published this page.