Capt. James Gadsden, a U.S. Army engineer and the aide-de-camp to Maj. Gen. Andrew Jackson, spent this day 200 years ago surveying the remains of the British Post (or “Negro Fort”) at Prospect Bluff on the Apalachicola River. He had been ordered to design and build a new American fort on the site.
This article is part of our continuing series: Seminole War 200th Anniversary.
The original fort at Prospect Bluff had been built by the British during the War of 1812 as a supply depot and training base. Gadsden, in fact, was surprised by the size and strength of the ruined works that he found there. The central citadel – an octagonal structure with 18-foot thick walls – had been blown up when a U.S. cannon shot ignited its powder magazine on July 27, 1816. The blast scene and remnants of that central fortification were still evident but of no use from a military perspective. Other pa
rts of the original fort, however, were still largely intact.
Gadsden found a strong water battery – less its cannons, of course – still standing on the crest of the bluff. This structure was a redan or V-shaped fortification with its point directed at the river. The British had at first pierced the earthwork with two embrasures, one facing upstream and the other down, but later adapted the battery to mount four pieces of heavy artillery. Two of the guns, both 24-pounders, were aimed upstream while the other two, a 24-pounder and a 32-pounder, protected the downriver approaches. (Note: The terms 32-pounder and 24-pounder refer to the weight of the cannonballs fired by the guns). These were the cannon that had engaged U.S. Gunboats #149 and #154 at 5 a.m. on July 27, 1816. (Please see The Fort at Prospect Bluff and the video at the bottom of this page for the detailed history of the British Post or “Negro Fort”).
Vicente Sebastian Pintado, the Spanish Surveyor-General for West Florida, visited the fort before the British evacuation in the spring of 1815. He reported that the water battery was made of “wood and mud.” If the walls were designed in the same method as those of the citadel, then they were made by packing mud or earth between two walls of timber. [I]
The flanks of the water battery were protected by log stockades that ran inland from the river to the octagonal citadel:
…About sixty yards in there is an octagon of logs of wood packed with solid earth with care, which has exterior sides of about 50 feet; but this was not finished, only the rampart, for the merlons and the esplanade were underway when the news of peace was received. They had a shallow ditch. The Octagon and houses of the establishment, which in the greater part consist of a considerable number of cabins, is encircled by a stockade of not much strength, leaving open the part along the river. [II]
Gadsden’s map of Prospect Bluff shows this stockade to have angular in design, with the “Octagon” or citadel serving as its points and the legs of the arms resting on the river above and below the water battery. It is not clear whether this stockade remained intact by 1818 or if it had been destroyed by the explosion and subsequent burning of wooden parts of the fort by U.S. troops two years earlier. [III]
Beyond this stockade was an extensive breastwork or entrenchment that surrounded the entire complex. Pintado described it as “a shallow ditch and earthen parapet, of little depth the one and the other of little height, in the manner of a field entrenchment.” Gadsden’s survey showed it to be roughly rectangular in design with full bastions on the interior or eastern corners and demi-bastions on the river side. Despite some modern artistic representations, it did not extended along the crest of the bluff to completely enclose the work.
Work appears to have continued on this outer entrenchment after Pintado saw it. Much of it is beautifully preserved today – more than 200 years after it was built – and some of the surviving wall sections are more than 15-feet thick. The corner bastions were elevated and of more substantial construction and undoubtedly were designed to serve as emplacements for field artillery. Traces of the prepared cannon positions are still visible.
The entire British complex covered more than 12-acres, with the citadel or interior octagon its the strongest point. Since this part of the fort had been destroyed by the explosion that killed 270 men, women and children, Capt. Gadsden decided to built a completely new fort within the outer British entrenchment. The new post would garrison far fewer men than the British fort and did not need to be of its massive size.
With a good understanding of the nature and extent of the surviving British defenses, the engineer began work 200 years ago tonight to design the new fort that would be built by the men of Jackson’s army over the coming week. The commanding general would be so pleased by his young engineer’s work that he would name the post Fort Gadsden in his honor.
This series will continue. You can read other articles by visiting Seminole War 200th Anniversary.
This free documentary from Two Egg TV tells the true story of the “Negro Fort” at Prospect Bluff:
[I] Vicente Sebastian Pintado to Senor Don Josef de Soto, April 29, 1815, Pintado Papers, Library of Congress.
[III] Plan No. 4, included in Capt. James Gadsden to Maj. Gen. Andrew Jackson, August 1, 1818.