One-Way Mission of the H. L. Hunley

By Brian Hicks

Dixon’s secret weapon was the H. L. Hunley , a 40-foot, hand-powered submarine moored at the Battery Marshall dock on Sullivan’s Island. And in truth, she was no longer much of a secret. In the past six months, the sub had dominated Charleston gossip. She had arrived in August with the promise that, finally, the blockade would be broken. But after little more than a week the Confederate military seized the craft and promptly sank her. Five men died.

Dixon came to Charleston after that. Horace Hunley, the submarine’s namesake, had convinced General P. G. T. Beauregard, commander of the Department of South Carolina, Georgia, and Florida, to return the Hunley to him. With a simple telegram, Hunley raised an entire crew of volunteers from Mobile, Alabama. He was wise enough to put Dixon in charge. The former riverboat engineer, a member of the 21st Alabama Infantry Regiment, had helped build the torpedo boat and understood her better than most. While recovering from a serious wound, Dixon was working in the Park and Lyons machine shop in Mobile when the Hunley and one of her predecessors were under construction there. The lieutenant had been shot at Shiloh in April 1862; the bullet meant for his thigh hit a $20 gold coin in his pocket, warping it and mangling his leg. But the coin saved his life.

Dixon not only gained a pronounced limp, but also a good luck charm. He had the coin engraved with the date of the battle and the inscription “My life preserver.” Now, he carried the reminder of his unbelievable luck with him everywhere. He hoped that good fortune would linger a little longer—more than it had for Hunley.

In October Horace Hunley had attempted to pilot the sub in Dixon’s absence. With a crowd watching the demonstration from onshore, he sank the submarine in Charleston Harbor, killing himself and seven others. The sub’s death toll was at 13, none of them Union sailors. After that, it had taken Dixon a month to convince Beauregard to let him try again.

By then many had dismissed the submarine as just another failed experiment, another lost cause. Dixon would change that perception on this night. The Hunley would sail in five minutes.

Early Efforts

The submarine age arrived 150 years ago, due mostly to an ambitious daydreamer, two years of research and development, and a war. Men had built underwater craft before the Civil War, but those submarines never actually accomplished the goal for which they were built—they never sank an enemy ship in battle. The Hunley ’s feat was so far ahead of its time that it would not be repeated for half a century.

Horace Lawson Hunley, the daydreamer, was successful by almost any measure. He was an attorney, a former state lawmaker, deputy chief of customs in New Orleans, and friends with some of the city’s most influential men. Hunley had made a modest amount of money, enough that he owned a small plantation and a few slaves. In late 1861, he decided to expand his business portfolio.

He may have gotten the idea to build a submarine in the summer of 1861. The Reverend Franklin Smith, a chemist and inventor, had sent a letter to Southern newspapers, urging businessmen to invest in the idea of “Submarine Warfare.” Smith wrote that “The new vessel must be cigar shaped for speed—made of plate iron, joined without external rivet heads; about thirty feet long, with a central section about 4 x 3 feet—driven by a spiral propeller.”

Later, many would assume that patriotism drove Hunley. In truth he thought the war was foolish but suspected it could be good for business. The Confederate government and wealthy businessmen were offering rewards of up to $50,000—the 19th-century equivalent of $1.3 million today—to anyone who sank a Union warship. But there was more to it than money. Hunley wanted to be a part of something bigger; he dreamed of being a Great Man. He carried a notebook in his pocket, a ledger in which he wrote grandiose ideas to make a mark on this world. Eventually, Hunley discarded all those dreams and adopted Smith’s.

In the fall of 1861, Hunley, with financial backing from several friends, contracted New Orleans engineer James McClintock to build his submarine. He could have hardly found a better partner. A native of Cincinnati, McClintock had been one of the youngest steamboat captains on the Mississippi before settling down to open a machine shop just outside the French Quarter. At 32, he was considered an engineering prodigy. McClintock recently had been contracted to make bullets for the Confederate Army, mostly because he built a machine that could produce thousands of minié balls per hour.

McClintock designed and built his submarine that winter, and she apparently was modeled exactly on Smith’s letter. The boat, which was christened the Pioneer , was 35 feet long and almost completely round—four feet wide and four feet tall. She had a single hatch and two short, squat fins that the pilot could adjust to dive or surface. Her tapered ends served as ballast tanks to take in and expel the water needed to submerge and surface. Two men turned a crank to power the sub’s propeller, while a third stood, his head in the hatch, and steered.

The Pioneer was launched in March 1862, around the time the Monitor fought the CSS Virginia to a standstill at Hampton Roads. The sub proved fragile, slow, and leaky, but she worked. The Pioneer eventually became the only submarine to receive a letter of marque—a privateer license, basically—during the Civil War. But she would never see combat.

In April 1862, Union forces captured New Orleans. Hunley and McClintock, worried that their secret weapon would fall into enemy hands, sank the Pioneer and escaped to Mobile. There, Confederate District of the Gulf commander Major General Dabney H. Maury took an interest in the pair’s efforts and introduced them to the owners of the Park and Lyons machine shop. It would take nearly a year to build their second submarine, the American Diver .

McClintock, wanting to improve on the Pioneer ’s design, wasted months trying to build an electromagnetic engine to power the American Diver (the engineer thought manually cranking the propeller was primitive). But he could not build an engine small enough to fit in his boat. Finally, McClintock had to give up and install cranks. He made the sub only a foot longer than the Pioneer but added two men to the crew complement, hoping more manpower would make this sub faster than the last one.

The Diver attempted only one attack on the West Gulf Blockading Squadron, and it was a disaster. Once the sub was untethered, she didn’t have enough power to fight the tide and her crew found themselves being pulled out to sea. They never attempted to engage the blockade; it was all they could do to make it back to the dock. Before they could try again, the boat was swamped under tow and sank in Mobile Bay.

A Sleek, Complex Vessel

With the loss of the American Diver , Hunley and McClintock were out of money. They would have been forced to give up their dream except that Edgar C. Singer, a torpedo expert from Texas, arrived in Mobile that spring. Singer recognized the importance of the project and found McClintock the money he needed to go back to work.

Throughout the spring and early summer of 1863, McClintock and workers from Park and Lyons built a third sub, far more advanced than its predecessors. Years later, McClintock would write that this time he took “more pains with her model, and the machinery.”

She would have an “elliptic shape.” The bow would be only an inch wide, the submarine expanding to her broadest point at the crew compartment and tapering again toward the stern. McClintock added thin dorsal fins in front of the hatches to cut down on drag. He also installed small fins in front of the boat’s diving wings to deflect rope or seaweed—anything that might jam the fins’ operation. This was not a cigar boat; she looked more like a shark.

At 40 feet, the sub would be four feet longer than the Diver . The reason, McClintock said, was because “[t]his boat was built expressly for hand power.” If she had to be powered by hand, he would simply add more hands. The main compartment of the submarine would be nearly 25 feet long. With that additional space, the sub could carry a crew of eight. McClintock expanded their power exponentially by installing a series of reduction gears and a flywheel between the propeller and hand cranks. The crew would be able to propel the sub like a wind-up toy. This would give the men periods of rest, and perhaps even allow them to work in shifts. It would cut down on exhaustion, which he hoped would increase the submarine’s range.

McClintock also improved the plumbing in this submarine. She would include forward and aft ballast tanks, as the others had, each with its own pump. But this time he added fail-safe redundancies with a network of pipes running beneath the crew bench. With the switch of a lever, water could be pumped from one tank to the other, equalizing water distribution. The pumps also served as back-ups to one another and could siphon water from the crew compartment. This was perhaps the boat’s greatest safety feature. The sub’s buoyancy was fragile; a few inches of water in the main compartment, and she would sink to the bottom.

The first draft of history would call this submarine a converted iron boiler, but that was not the case. McClintock designed a sleek, hydrodynamic, complex vessel far ahead of her time. Well into the 20th century, most boats that traveled beneath the waves followed McClintock’s vision, but he would never be recognized as the father of the modern submarine.

The H. L. Hunley was launched in July 1863. A crew likely composed of men from the Park and Lyons machine shop tested the boat in the Mobile River for a couple of weeks. Finally, on 31 July, they invited Confederate officials to a demonstration. General Maury, Rear Admiral Franklin Buchanan, and Brigadier General James E. Slaughter gathered onshore, their attention directed to a flat barge anchored in the river.

On cue, the Hunley appeared upstream towing a floating contact mine at the end of a long line. As the sub approached the barge, she gracefully slipped beneath the water. The mine stayed on the surface and, when it made contact, there was a tremendous explosion. The barge lurched and dipped and soon began to sink. Several minutes later, the Hunley surfaced 400 yards downstream.

Confederate commanders in Mobile soon were recommending the submarine for service at Charleston. Buchanan, commander of the Naval District of the Gulf, likely orchestrated the campaign. The admiral did not trust submarine technology, but military politics also played a role. The Hunley , although a civilian vessel, had been promoted tirelessly by the Confederate Army—and Buchanan had no control over her. To rid himself of the problem, he sent a note to the commander of naval forces in Charleston, Flag Officer John Randolph Tucker, enthusiastically recommending the Hunley .

“I am fully satisfied it can be used successfully in blowing up one or more of the enemy’s Iron Clads in your harbor,” Buchanan wrote. The admiral added a request that Tucker forward his suggestion to Beauregard at his Charleston headquarters. The general responded almost immediately. He needed the Hunley . Charleston needed the Hunley .

In less than two weeks, the submarine arrived there by train. And then, tragedy. The sub sank twice, 13 men died, and the city lost hope. By the winter of 1864, Dixon was the only man left with faith in the boat. And he would not fail.

To Sink a Blockader

It took the Hunley nearly two hours to reach the Housatonic on 17 February 1864. Running with the tide, the submarine traveled at about 4 knots. Dixon steered by compass; from his vantage point low on the water, he likely could not see a ship miles away. The boat traveled on the surface, as Beauregard had asked Dixon not to dive. This was the only thing that gave the lieutenant pause. The Hunley recently had been refit with a 20-foot spar tipped with a torpedo. Instead of diving beneath a ship and towing a contact mine into her side, the submarine would ram her prey with the torpedo. After completing the mission, Dixon would flash a blue phosphorus lamp, the signal for troops ashore to start a signal fire by which the lieutenant would steer the Hunley home.

As they sailed into the Atlantic, the grind of the crank and reduction gears became a monotonous noise that filled the compartment. The crew said little; talking used oxygen, and that was a commodity they could not spare. Despite the boat’s deadly history, Dixon had found more than enough volunteers in Charleston—sailors, artillerymen, even some veterans of privateers. Throughout the winter these men trained, and those two months of practice made them the most proficient crew ever to sail the sub. In that time, the Hunley had gone out three or four times a week, sometimes getting close enough to blockaders that Dixon could hear sailors singing on deck. But they had never attacked. Conditions had never been quite right.

By 2020, Dixon could see the Housatonic less than a quarter-mile away. He knew that he should wait for the tide to turn, to make it easier to return to shore. But they were in enemy territory now; to wait risked detection, and stealth was their greatest advantage. Besides, Dixon had been waiting for months. He could not wait any longer.

On board the Housatonic , there was little activity that evening. Nine sailors were milling about on deck, settling into a long shift. The watch had changed at 2000, and the men who had just arrived topsides were still adjusting to the cold. Most of the 155 sailors on board were belowdecks.

Life on board the Housatonic was about as dull as it got in the South Atlantic Blockading Squadron. The 205-foot sloop had arrived off the coast of Charleston in late September 1862 and since then had seen little action. The Housatonic ’s primary role was to stop blockade-runners trying to reach the city. On this night, the ship was at just about the northernmost post in the blockade, not exactly a key position.

The first man to notice the strange thing in the water was Robert F. Flemming, a black landsman standing watch on the ship’s cathead. Just before 2030 he saw something about 400 feet off the starboard bow, approaching from land. The object appeared to be about 22 feet long, he later recalled, with only its ends visible. Water washed over its midsection, but parts of it stood nearly two feet out of the water. Flemming alerted the officer of the forecastle, Acting Master’s Mate Lewis A. Comthwait, who studied the object for only a second before he dismissed it as floating debris. “It’s a log,” he said.

“Queer-looking log,” Flemming replied. He noted that this “log” was not floating with the tide—it was moving across it.

Flemming called out to C. P. Slade, another black sailor on watch. By this time the object was only 300 feet from the ship and moving too fast to be drifting. Flemming told Slade there was “a torpedo coming.”

The crew of the Housatonic had heard stories of the Confederates’ alleged secret weapon. After receiving several reports from Confederate deserters, the Union squadron commander, Rear Admiral John A. Dahlgren, had issued orders the month before for ships to prepare for attacks from boats that could travel nearly or completely underwater. This intelligence was the reason the Housatonic, like all the squadron’s blockaders, anchored in relatively shallow water with her fires stoked and pressure in her boilers. The ship was ready. Flemming was ready, too, even if nobody else was.

“If no one is going to report this,” he said, loud enough for the other men on deck to hear. “I will cut the buoy adrift myself and get ready for slipping.”

When Comthwait heard Flemming’s remark, he took another look, this time using binoculars, and saw that this log had two lumps on it the size of a man’s head. Water rippled around the lumps, and he realized the object was moving under its own power. Comthwait turned and ran aft to find the officer of the deck.

By then, nearly every man on watch had spotted the Hunley , including Acting Master John Crosby, who alerted Captain Charles Pickering. On deck within seconds, the captain quickly called out orders—“Slip the anchor chain and fire up the engine”—and got his first look at the fish boat.

“It was shaped like a large whale boat, about two feet, more or less, under the water,” Pickering later recalled. “Its position was at right angles to the ship, bows on, and the bows within two or three feet of the ship’s side, about abreast of the mizzen mast, and I supposed it was then finding the torpedo on.”

Pickering ordered his men to “go astern faster,” raised his double-barrelled shotgun, and fired two loads of buckshot at the strange boat. Several of the crew joined him. They shot at her for more than a minute with small arms; the sub was too close to train cannon on her. Some of the men aimed at faint lights on her top that appeared to glow, candlelight filtering through the sub’s deadlights. The gunfire did no damage to the dark craft so far as they could tell.

And then, an explosion. Crosby would later say it “sounded like a collision with another vessel.” There was no smoke, no flame, no sharp report, no column of water thrown into the air—simply a noticeable pressure, and then the Housatonic blew up.

The men on deck were still firing on the Hunley when the explosion knocked them off their feet. The ship lurched violently to port, recoiling from the blow. Deck planks were blown nearly as high as the ship’s mizzenmast. One sailor saw furniture floating out of a ten-foot hole in the side of the ship.

The Housatonic was going down fast. But because the sloop had been anchored in such shallow water, she did not have far to go. When her keel hit bottom, about 25 feet down, most of the ship’s rigging still stood high above the waterline. Sailors climbed into the lines to await rescue. Pickering, who had been blown off his feet, told Crosby to take a lifeboat and pull for the nearby sloop Canandaigua for help.

While they awaited rescue, Robert Flemming, the man who had first spotted the Hunley , was among the sailors clinging to the ship’s rigging. After about 45 minutes he spotted the Canandaigua in the distance, some 800 feet away, making good time toward them. And then he saw something else. Later, Flemming would simply say, “I saw a blue light on the water just ahead of the Canandaigua , and on the starboard quarters of the Housatonic .” For more than a century, men would speculate that Flemming, the first Union sailor to see the H. L. Hunley , was also the last man to see her for more than a century.

The Mysterious Aftermath

It would be days before Charleston realized the Hunley was missing, and about a week before Confederate officials learned that the torpedo boat had actually sunk a blockade ship. By then, the surviving crew of the Housatonic were preparing for an inquiry that would eventually conclude there was nothing they could have done to avert the loss of their ship.

But what happened to the Hunley ? Was she struck by the Canandaugua , left rudderless and adrift? Did the concussion of the explosion knock the crew unconscious or, worse, kill them? Did one of the sailors on the Housatonic crew shoot out a port in the forward conning tower, allowing the sub to fill with water and sink? Or did Dixon simply set the sub down on the bottom to await the turning tide, and there the crew ran out of air? There are dozens of theories, and conflicting clues. The answer may never be known.

For a while, the Confederates maintained a ruse that the Hunley had returned to port, suggesting she still lurked among the South Atlantic Blockading Squadron. But Dixon and the world’s first attack submarine were on eternal patrol and would not surface again for more than 130 years.


This article is adapted from a forthcoming book on the H. L. Hunley ’s history and Clive Cussler’s 15-year search for the submarine. It was pieced together using letters, official Confederate documents, and first-person accounts. A letter from George E. Dixon to his friend Henry Willey dated 31 January 1864 (a copy of which is held by the Friends of the Hunley , ) provides many details, as does a letter Dixon wrote to Captain John Cothran of the 21st Alabama on 5 February 1864. William Alexander, a Mobile engineer who helped build the submarine and served in the final crew until two weeks before her famous mission, told various versions of the Hunley tale in a series of articles published around the turn of the century, beginning with “The True Story of the Confederate Submarine Boats” ( New Orleans Picayune , 29 June 1902). Alexander’s accounts provide most of the meat to a story that is largely cryptic in official military and naval records. The rest of the account comes from the Official Records of the Union and Confederate Navies in the War of Rebellion , particularly Series 1, Volume 15. The National Archives also holds many Hunley -related documents, not the least of which are records of the official naval court of inquiry into the sinking of the Housatonic . Several letters of Horace Lawson Hunley survive in the Archives and are most accessible in Ruth H. Duncan’s book The Captain and Submarine CSS H. L. Hunley (Memphis: Toof, 1965).

Solving the Enduring Hunley Mystery

By Brian Hicks

For 150 years, no one has been able to answer the single most important question about the H. L. Hunley : Why did she sink?

Since the submarine was recovered from the Atlantic floor in 2000, scientists have found dozens of tantalizing, sometimes conflicting clues about what happened to the boat following her attack on the Housatonic . But there’s been no smoking gun, no single piece of evidence that could solve the lingering mystery of what happened in the Hunley’s final moments.

But that could soon change. This spring scientists will embark on two separate projects that should give new insights into the submarine’s last hours. One is a simulation of her February 1864 battle using new information found by the Hunley ’s conservators. The other is the beginning of the final phase in the sub’s conservation and restoration.

In March the Hunley will be submerged in a tank of caustic chemicals that will slowly extract the salt that seeped into her iron hull over the 136 years she was in the sea. After three months in this soak, scientists will begin the six-month job of deconcretion. A thick layer of sand and shell built up on the sub’s hull during her time buried beneath the ocean floor. Scientists have left this hard shell—a concrete-like substance called concretion—on the sub to protect her hull and minimize its deterioration. That decision helped to stabilize the boat while her interior was excavated, but the trade-off has been that the Hunley ’s hull has never been examined. Now archaeologists will finally have the chance to see if there is damage that might shed light on her sinking.

Scientists believe a few months in the chemical soak will loosen the concretion enough to remove it, but the process could take far longer. All of the buildup must be removed before the conservation process can proceed. After that, it’s expected the Hunley will have to soak three or four more years before she’ll be ready for display in a museum.

As conservators scrape the hull, archaeologists at Clemson University’s Warren Lasch Conservation Center are planning the simulation of the Hunley ’s battle with the Housatonic . In the past year, new clues have emerged that change the story dramatically.

Conservators working to preserve the submarine’s 20-foot spar discovered remnants of the Hunley ’s torpedo still attached to its end. Most historical accounts suggest the Hunley speared a barbed torpedo into the ship’s hull and then backed away. The torpedo was then detonated with a line from the explosive that pulled taut when the sub was a safe distance away. But when scientists found copper sheeting—the skin of the torpedo—still bolted to the spar, it suggested a very different scenario. It now appears the Hunley used its spar like some other Civil War vessels, by simply ramming an enemy ship with a torpedo that blew up on contact.

And that means the Hunley was only 20 feet away from the blast that sank the Housatonic . “We want to see what we can learn from that about how it might have impacted the submarine as well as the crew,” said Stéphanie Cretté, director of the Warren Lasch Conservation Center.

The results of the simulation will be compared to the submarine and the data collected on the remains of the crew, which were buried in 2004. Forensic tests have revealed much about the men who served in the Hunley —some of them had bad backs, for instance, others had suffered broken bones—but there was nothing that proved they suffered any sort of trauma the night of the attack.

The work planned for the Hunley this year could be the most revealing since the initial excavation of the submarine in 2001. The sub, which was discovered in 1995 by best-selling author Clive Cussler’s National Underwater and Marine Agency, was raised by South Carolina’s state Hunley Commission and the non-profit Friends of the Hunley on 8 August 2000. Since then, she has resided in North Charleston at the Warren Lasch Conservation Center, named for the Friends’ first chairman.

During the initial excavation, which lasted four months, scientists discovered hundreds of artifacts—including Lieutenant George Dixon’s gold coin. Everything found inside the submarine was mapped on a three-dimensional grid so that each detail of the archaeology would be preserved.

So far, many of those discoveries have proven contradictory. The sub was filled with mud and sand, but it remains unclear when the hull was breached. There is evidence that no sand penetrated the boat for at least six months after the attack. Also, there were stalactites on the sub’s ceiling, which means that at least part of the interior was dry for a long time. Still, the submarine could have been partially filled with water soon after she sank, as some evidence indicates.

Cussler believes the reason the Hunley sank may lie with the shroud around the submarine’s propeller. Half the shroud is missing, but the half that remains has a couple of distinctive triangular cuts in it that look a lot like propeller strikes. Cussler points out that the last reported sighting of the submarine, by Housatonic crewman Robert Flemming, put her directly in the path of the screw sloop Canandaigua . Cussler believes the ship could have hit the Hunley , severing her rudder and knocking the sub off an even keel. The rudder was found near the boat, but not attached to her.

If there are clues that can dispel or support theories about her mission, chances are they will be found later this year. And then, finally, scientists may have the answer to that nagging question: Why did the Hunley sink?



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