Case Study: Fort Jefferson

Case Study: Fort Jefferson

Words: Lisa Stegeman
Photos: demerzel21, benkrut, wilsilver77, bennymarty, boogich

As the sun rises over blue waves of the Gulf of Mexico, molten orange sunlight illuminates the eastern wall of Fort Jefferson, a beacon of American Naval power and ambition since its construction was completed in 1875. From start to finish, 16 million bricks made their way through workmen’s skillful hands and into the 16 acre masterwork that stood tall as the largest brick building in the western hemisphere.

Well, technically it stands more wide than tall, as the walls of its hexagonal shape can reach about 100 meters across. What is now the national park of the area spans about 100 square miles, with a shocking 98% of it underwater. This short and stocky structure is more than it may seem; before its final military abandonment in 1906, it housed around 1,700 military personnel, complete with lighthouse, barracks, rainwater cisterns, and cannons. Its humble beginnings were not so much humble as they were ambitious, and we will soon learn that ambition can take you very, very far. Too far, perhaps.

In 1826, after the U.S. purchased what would soon be the state of Florida from Spain for a hefty 5 million dollars, construction wrapped on Bush Key, later renamed Garden Key; this plot would be the site of Garden Key Light, the 65-foot tall lighthouse complete with a houseman’s cottage that unknowingly opened the door for millions more bricks to become a piece of history. 

That same year, U.S. Navy Commodore David Porter set his watchful eyes upon Dry Tortugas. A small, pitiful span of seven small islands, all sand and lush greenery, about 140 acres all together, it was decidedly unworthy of military use. That is, until Commodore John Rodgers anchored the survey ship Florida on its sandy banks. Impressed with its potential, he rallied for its use in keeping an eye on the Gulf, though they would need to rely on heavy naval power to defend the island. Luckily for the Navy, heavy fire power was exactly what the fort was designed for. Thanks to Robert E. Lee, the island was then reserved for military use after he wrote Thomas Blake, Commissioner of the General Land Office, sharing his high opinion of the island. Construction of the fort began that very year.

The design of the fort called for two-tiered gun rooms called casemates, which housed 150 guns each. These incredible structures were built hosting mounted guns and were tucked in behind armored walls. From the inside of a casemate, the sound of gunfire reverberates like a supreme echo, with the kind of booming sound that shakes your bones. 

To build these rooms, carpenters built wooden arches and frames, then masons bricked on top of the frames, slowly crafting the heavy arches plotted throughout the fort. The geometry of the arches and hallways lines up in such a way that looking down the hall looks like gazing down an endless shaft of brick, mortar, and stone. To stand inside this gargantuan fortress is to stand within the belly of a beast.

Fort Jefferon’s hexagonal shape offers a 360-degree vantage point of the island, essential for military success. Each of the fort’s six sides was fortified to provide essential backup to the U.S. naval fleet, with curtain walls and bastions where the walls meet. These bastions would each hold gunpowder magazines, a gunroom, and a magnificent granite spiral staircase whose technical and aesthetic beauty was likely never truly appreciated as it passed under countless unknowing boots. 

The U.S. Army had employed over 200 workers including civilian carpenters, career masons, general laborers, and, unfortunately, slaves in the fort’s construction efforts. The 16 million bricks mentioned before were supplied by the Pensacola firm Raiford and Abercrombie.

The image of hundreds of men assembling a massive fort on a picturesque island sounds quite beautiful, but this paradise was lacking one essential thing– fresh water. Surrounded by the salty blue water of the Gulf, they needed a solution and they needed it fast. Early into construction, a system of cisterns was added to the plan. These sand-filled columns stood at regular distances within the interior walls to catch rainwater and spout it into underground tanks for safe keeping. This is where their grand ambition comes in; these cisterns had a flaw, and that flaw was the first domino that brought the fort to its knees.

The warm, tropical rains that fell over Fort Jefferson in its first months began to erode these chambers, making all the collected water no longer potable but usable for cooking and cleaning. Luckily, plans added a set of steam condensers which distilled thousands of gallons of seawater, finally offering the workmen the crisp fresh water they needed. This desalinated water kept the workmen hydrated, but it also provided a breeding ground for mosquitoes, and in turn, disease. Yellow Fever would break out more than once within the fortress, only dampening the military efforts as tensions grew within the country.

When the American Civil War broke out, Major Lewis Golding Arnold’s command grew by over sixty men, who held the fort from enemy forces. The heavy guns were first fired on a brisk January day in 1861. By the end of that year, the fort would be home to over 300 soldiers, civilians, women, and children. That very September, the fort would gain one new member– its first prisoner. 

Fort Jefferson’s military prisoners were sent to this relatively new structure for crimes such as desertion and mutiny, and their sentences often included hard labor in the ongoing construction and maintenance efforts. In 1863, soldiers outnumbered these prisoners, but by late 1864, prisoner numbers grew past 800, almost double the soldier headcount, and eight prisoners escaped into the cold, unforgiving waters of the Gulf.

These prisoners and soldiers both would have manned the fort’s artillery, with some of the most advanced weaponry of the era. Its 15-inch Rodman smoothbores were the largest of the guns, needing seven men to fire a 400-pound projectile as far as three miles. Many of these guns still remain in the walls of the fort, though they were soon made obsolete by more advanced weapons created during and after the Civil War. 

On a hot summer day in July of 1865, four infamous prisoners walked into Fort Jefferson, two of whom would never walk out. They were Samuel Arnold, Micheal O’Laughlen, Edman Spangler, and Samuel Mudd, four men convicted of conspiring in the assassination of President Abraham Lincoln. These men would join the ranks of laborers continuing in the seemingly never-ending fort construction. After an escape attempt, Mudd was escorted past the prison and down into the dungeon. Adding insult to injury, the dungeon entrance bore the words “Whoso entereth here leaveth all hope behind” in a dark nod to Dante’s Inferno. Luckily, the dungeon was just a dungeon, no fire and no brimstone. 

After nearly a decade without many goings-on within the fort, the seawall was finally completed, including its 15-inch Rodman guns on the barbette tier. All in all, Fort Jefferson housed 243 large-caliber guns, many of which were never fired. 

Two years later, after many hurricanes and Yellow Fever outbreaks that killed soldiers, prisoners, and civilians alike including two famous prisoners, the War Department of the U.S. decided to remove the garrison. They left only a small force to hold the fort until 1889, when the Army gave the fort to the Marine Hospital Service to use as a quarantine station. 

Over the next nine years, hurricane winds and tropical storms ravaged the entire Key. Heavy rains eroded brick and stone, slowly tearing the structure apart at the seams. Vandals stripped whatever would come loose, and Fort Jefferson’s proud ruins would crumble under their own weight. 

In 1902, the property was given to the Navy Department, and all new structures they had added to the Key were destroyed in hurricanes over the next four years. The group of Keys was committed to a Federal bird reservation, and despite its still-crumbling husk, Fort Jefferson would become a hotspot for tourists and fishermen alike. In 1935, the fort became a national monument, and in 1992 it became a national park. Preserved after its prime, this structure made of millions of bricks by thousands of men is no longer a beacon of power, but a reminder of what used to be.

Today, tourists can take part in guided tours through the grand facility and see the remnants of ambition for themselves. After decades of disease epidemics, prisoner escapes, and unforgiving terrain, Fort Jefferson can still be described as “a dark, mean place,” as one fort resident once said. With its lighthouse decommissioned and barracks empty, the setting sun dims over raw brick, cold evening winds blowing silently through empty hallways, into abandoned gun rooms, and out into the cold air of the sea.

Sources:
Federal Writers’ Project (1939). Florida. A Guide to the Southernmost State. New York: Oxford University Press. p. 206.
Reid, Thomas. America’s Fortress. Gainesville: University Press of Florida. pp. 10–14.
Federal Writers’ Project (1939). Florida. A Guide to the Southernmost State. New York: Oxford University Press. p. 206.

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