Ships vs Forts 1861: Off to the Races

It was unthinkable for wooden warships in the long age of sail to engage massive forts mounting huge guns often firing heated shot plunging from the heights. Reliant on fickle winds for movement, they were sitting, flammable ducks.

Ocean sailors in large, deep-water vessels were (and are) never comfortable in shallow waters and narrow channels constricted by rocks, mudflats, and sandbars, washed by powerful surf, tides, and currents, and blown by shifting or onshore winds. Coastal and harbor maneuvering entails unique skills, experience, and risks. The U. S. Navy had little relevant experience when the Civil War began.

But technology was rapidly evolving. Steam and propeller (also called screw) propulsion, stouter hulls, and heavier artillery afloat evened the odds, generating new tactics and desperate clashes between ship and shore. The first significant Union naval engagement against a hostile coast occurred on August 28-29, 1861, in the strategically vital North Carolina Sounds.

Flag Officer Silas H. Stringham, commander of the Atlantic Blockading Squadron, led seven warships and two transports carrying 800 troops under Maj. Gen. Benjamin Butler. They were to plug the primary gap in the barrier islands at Hatteras Inlet through which Rebel raiders sallied forth to prey on Federal shipping.

Stringham’s squadron was a cross-section of the navy, led by two of the nation’s most modern and powerful warships, the wooden steam-screw frigates USS Minnesota and USS Wabash. In modern terms, they were mid-size warships like cruisers, larger than destroyers, smaller than battleships. These fearsome machines were about 300 feet long, 50 in beam, and sat 23 feet deep in the water with 650 officers and sailors each.

The frigates mounted around 40 8 to 12-inch smoothbore guns apiece. The Dahlgren 9-inch “soda bottle gun,” so-called for its shape, was the standard naval weapon and one of the best in the world. Capable of firing shot, shell, shrapnel, canister, or grapeshot, it weighed 9,000 pounds and could throw a 90-pound shot or 74-pound shell up to 3,500 yards.

The USS Susquehanna was an earlier model steam frigate with side paddle wheels rather than a propeller. She was almost as big, armed with 12 9-inch Dahlgrens and 2 newly patented Parrott rifles. Reflective of more scientific design and improved manufacture, the Parrotts could more than double the range of smoothbores but were prone to bursting and not fully trusted.

The steam-screw sloop-of-war USS Pawnee represented the smallest class of ocean-going combat ships, roughly equivalent to a modern destroyer. At 221 feet long, 47 feet wide, and 10 feet deep, she could more easily maneuver in constricted waters. She carried 8 9-inch Dahlgrens, 2 12 pounders, and 181 men.

These were traditional sailing vessels with “auxiliary” steam engines intended to supplement sails in low or contrary winds and in constricted waters. Steam technology was not yet sufficiently robust, reliable, or enduring to be the primary, much less the only, form of propulsion across vast oceans.

The USS Cumberland was a sail-only frigate unchanged in basic design for two centuries, a direct descendent of the USS Constitution, Old Ironsides. She was well armed with 21 Dahlgrens and a 70-pounder rifle, but powerless without good wind. A steam tug towed her whenever needed.

Warships were designed for ship-to-ship slug fests in blue water, not this type of operation. In March 1862, Minnesota would be hard aground in Hampton Roads and almost destroyed by the ironclad CSS Virginia (built on the hull and machinery of Minnesota’s sister ship, the former USS Merrimack) until rescued by the little USS Monitor with 2 guns. Cumberland would be rammed and sunk by Virginia.

The USS Harriet Lane was originally designed as a fast, side-wheel steamer to prowl the coasts for the Revenue Service, and thereby more agile, but more lightly constructed and armed with a few 24 and 32 pounders. The last squadron member, the USS Monticello, would join hundreds of civilian vessels acquired and converted to warships for the blockade. She was about the length of Cumberland but much lighter in civilian construction and armed with a 9-inch Dahlgren and 2 32-pounders.

This eclectic mix—frigates, sloops, and converted merchantmen, sidewheel, screw, and sail, of all sizes and shapes—would be employed in multiple combinations and numbers throughout the war.

Confederate forts Hatteras and Clark protected Hatteras Inlet. They were hastily constructed of timber frame, logs, and sand, armed with 10 and 5 guns respectively, and manned with some 700 soldiers. The guns were mostly light 32-pounders of limited range and inadequate for coastal defense.

Even with his powerful squadron, Flag Officer Stringham was cautious. The Rebels also had the narrow channel, sandbars, tides, currents, and shifting winds on their side. The key to safety of these mammoth machines was controlled and continuous motion. One lucky enemy shot could bring a mast down, disable a rudder or propeller, penetrate a hull to blow up a boiler, or destroy the engine. Sitting duck.

Stringham invented a simple but revolutionary tactic, possible only with steam propulsion. Rather than closing with the shore and anchoring to engage the forts, he kept his ships moving in a loop, in to fire broadsides and out to reload (with the tug towing Cumberland). The era’s guns could not adjust rapidly in train or elevation to targets moving faster than a soldier could march. A naval broadside was aimed primarily by steering the vessel parallel to the target.

Fort Clark’s return fire was ineffectual, falling short or passing over, and scoring no hits. The defenders exhausted their ammunition and abandoned the works. Monticello approached Fort Hatteras, but ran aground and took five hits, none serious. Finding his bigger guns of longer range than the fort’s, Stringham anchored his ships, pounded the Rebels into submission, and the army took possession.

In November 1861, the process repeated on a larger scale against Forts Walker and Beauregard in Port Royal Sound, South Carolina, between Savannah and Charleston—one of the finest natural harbors on the east coast. The navy required Port Royal as a haven and support base for blockaders. Flag Officer Samuel F. DuPont commanded the newly organized South Atlantic Blockading Squadron, accompanied by 13,000 troops under Brigadier General Thomas W. Sherman.

DuPont’s 77 warships, transports, and supply vessels constituted the largest fleet under the American flag to date. The main battle column of 9 warships would be led by frigates Wabash and Susquehanna, followed by 3 steam sloops-of-war including Pawnee, 1 sailing sloop towed by a converted gunboat, and three purpose-built gunboats, Unadilla, Ottawa, and Pembina. The term “gunboat” applied to almost anything afloat with a gun and smaller or lighter than frigates and sloops.

The navy issued emergency contracts for purpose-built, shallow-water warships. They were schooner-rigged, wooden-hulled, steam-screw “ninety-day gunboats,” 158 by 28 by 9 feet, with crews from 60 to 114, armed by 3 to 5 smoothbores and rifles. Twenty-three ships of this class would be rapidly but soundly constructed and would serve well.

DuPont’s second, flanking column consisted of five civilian conversions, mostly coastal cargo/passenger steamers similar in size, but not construction, to the frigates and armed with up to nine guns.

Confederate Brig. Gen. P. G. T. Beauregard advised Governor Francis Pickens that Port Royal Sound could not be defended as forts on opposite sides would be too distant for mutual support. Overruled by the governor, Beauregard designed Fort Walker on Hilton Head Island opposite the eponymous Fort Beauregard on the north shore, flanking the entrance.

These forts, again, were hastily constructed of wood and sand, under armed, and incomplete. Beauregard planned to arm Walker with 7 10-inch Columbiads. One of the best seacoast weapons, the 15,400-pound, cast-iron gun could lob a 128-pound shell to 4,800 yards or solid shot to 5,600 yards.

But Columbiads were not available, so the general substituted 12 smaller caliber guns and a single 10-inch, which required additional space behind the parapet; the traverses at the ends were unfinished, exposing the flanks to enfilade. Another 10 guns guarded against land assault from the rear and right flank. The garrison was 1,800 soldiers and artillerymen. The isolated Fort Beauregard on Philip’s Island was more lightly armed and manned with 640 men.

Flag Officer DuPont assembled his warships at New York, soldiers and transports at Annapolis, and coal and ammunition ships in Hampton Roads. The fleet merged in Hampton Roads and put to sea on October 28, 1861, with the New York Times front page trumpeting “The Great Naval Expedition” and listing full order of battle down to regimental for all to see.

Nearing the North Carolina coast, a fierce gale scattered the formation, sinking or driving ashore three food and ammunition ships and a transport carrying 300 Marines; all but seven sailors and Marines were rescued. General Sherman advised DuPont that his soldiers could not land and assault the forts until additional ammunition and landing boats arrived on ships still straggling in. They would not appear until after the battle. The Flag Officer would proceed anyway on November 7, 1861.

 

DuPont adopted Hatteras Inlet tactics: the battle line would enter mid channel engaging both forts—Walker to port (left), Beauregard to starboard (right). Once passed the forts, the column would execute a port turn, concentrating on Walker on the way out, then turn again and repeat. It was a racetrack; they were off to the races. Meanwhile, the five converted gunboats of his flanking column would proceed up channel and fend off the bunch of small Confederate gunboats known as the “mosquito fleet.”

Flagship Wabash with the flag officer aboard led the column, followed by the other frigates, sloops, and gunboats. Having jettisoned her guns to survive the storm, the steam gunboat Isaac Smith was unarmed, so she towed the sailing frigate Vandalia.

Fort Walker opened on the approaching enemy at 09:26. Their first shot harmlessly exploded shortly after leaving the muzzle but set off a storm of fire on both sides. Incoming shells blasted into the fort in geysers of sand and woodchips, although many passed overhead to strike well beyond. Struggling to adjust their aim on moving targets, Rebel gunners generally missed or overshot also, sending rounds into the ship’s rigging.

The column held formation through the first turn, when Commander Sylvanus W. Godon of the sloop Mohican, third in column, saw that he could enfilade Walker without danger of return fire. He pulled out of line, stopped on the fort’s left flank. The rest of the column followed Mohican and bombarded away while Wabash and Susquehanna continued for a second and third pass around the track.

Delayed by the storm, the converted gunboat USS Pocahontas pulled in and joined the fray commanded by Commander Percival Drayton. His brother, Brig. Gen. Thomas F. Drayton, was in command at Fort Walker. Brother against brother.

By 2:00 p.m., most of Walker’s guns were disabled or dismounted and almost out of ammunition; Rebels evacuated the fort and fled inland. Commander John Rodgers rowed ashore under a flag of truce and raised the Union flag. Seeing this, and knowing they could be trapped, Rebel troops in Fort Beauregard abandoned their works.

The South suffered 11 killed, 47 wounded, and 4 missing while in the Northern fleet, 8 were killed and 23 wounded. Union forces occupied Beaufort and moved north into St. Helena Sound up to the rivers south of Charleston, beginning the siege of that city.

Du Pont and Sherman saw that Port Royal’s fall had potential far beyond serving as a blockading base: “the occupation of this wonderful sheet of water, with its tributary rivers, inlets, outlets, entrances and sounds, running in all directions, cutting off effectually all water communications between Savannah and Charleston, has been like driving a wedge into the flanks of the rebels between these two important cities.”[1]

Confederate President Davis agreed dispatching General R. E. Lee to take charge of coastal defenses. Lee reported: “I have thought [the enemy’s] purpose would be to seize upon the Charleston and Savannah Railroad near the head of [Port Royal Sound], sever the line of communication between those cities with one of his columns of land troops, and with his other two and his fleet by water envelop alternately each of those cities. This would be a difficult combination for us successfully to resist.”[2]

Lee improved fortifications and built up a defense in depth around Savannah with what forces he could muster. The Rebels blocked Federal land advances in the area for two and a half years; no attempt was made to exploit the potential for further joint operations.

The Battle of Port Royal was a revelatory moment in naval warfare, but one not repeated in this war because the conditions—a broad, deep, sound in which to maneuver—did not reoccur. Hatteras Inlet and Port Royal were successful navy shows against weak sand and wood forts.

Future posts will discuss actions against massive masonry forts at New Orleans, Charleston, and Mobile—harder nuts to crack—and the unique challenges of river forts like Henry, Donelson, and Island No. 10, and the mighty citadel at Vicksburg, while Fort Fisher at Wilmington deserves its own story.

[1] John D. Hayes, ed., Samuel Francis Du Pont: A Selection from His Civil War Letters, vol. 1, The Mission: 1860– 1862 (Ithaca, NY, 1969), p. 285.

[2] R. E. Lee to General S. Cooper, January 8, 1862, OR, Ser. 1, vol. 6, p. 367.